The invention relates to the field of fluid transfer devices and, more specifically, to a novel intravenous drug access system.
The manipulation of fluids for administration to a patient in hospital and medical settings involves the use of drug access systems that typically include a sealed inflatable container, commonly referred to as an intravenous (IV) bag. The IV bag is used to store a primary liquid such as plasma, blood, saline, or other types of medicinal solutions. When fluids are to be introduced into a patient intravenously, an IV bag is suspended above the patient on a portable hanger stand. Through a series of tubes and connectors, the fluid within the IV bag is delivered from the IV bag to the patient.
FIG. 1 illustrates a partial perspective view of a traditional IV bag 100. The IV bag includes a sealed inlet or injection port 102 and an outlet port 104 for the transfer of fluids to and from the IV bag, respectively. The inlet port 102 permits the introduction of a secondary fluid, such as a drug, into the IV bag, for mixing with the primary fluid. The outlet port 104 permits the transfer of the primary solution in the IV bag to the patient via tubes and connectors.
To seal the contents of the bag, the inlet port 102 typically includes a septum 106 compressively affixed within the interior opening of the inlet port to prevent the flow of fluid out of the bag. The septum 106 may be of continuous construction or made with a pre-fabricated slit that remains closed until penetrated. In either case, the septum is sufficiently resilient so as to permit penetration of the septum with a sharp device such as a syringe needle for the transfer of fluids into the IV bag.
Another example of a sharp device for penetrating a septum within an inlet port is a spiked connector. One type of spiked connector is a dual-spiked connector comprising a housing having a conduit extending from one spike to the other. The first spike is open-ended, in which the conduit communicates with the ambient. The second spike, at the opposite end of the connector, is closed such that the conduit is not in communication with the ambient. This closed-end tip is designed to break away and is used to penetrate the IV bag through the inlet port. At the first end, the open-ended spike is used to penetrate a drug vial containing a secondary fluid. By placing this dual-spiked connector between a drug vial and the W bag, a secondary fluid can be introduced into the IV bag and mixed with the primary fluid therein.
As a discrete pre-fabricated component, such a dual-spiked connector does not permit fluid flow therethrough because at least one spike includes a closed, break-away tip. However, upon penetration of the closed spike tip through the inlet port of the IV bag, fluid communication between the secondary fluid container and the bag may be established by breaking off the break-away tip while the tip is within the interior of the IV bag. Once the tip is broken, the conduit of the connector permits the flow of fluid in the internal fluid conduit from the drug vial to the interior of the IV bag. Disadvantageously, the break-away tip floats in the IV bag during the administration of the primary and secondary fluids to the patient through the outlet port. Should the break-away tip become lodged in the outlet port of the IV bag, the flow of the primary and secondary fluids to the patient may be stopped or dramatically reduced, endangering the health of a patient. Moreover, because the mixed solution in the IV bag is visible to the patient, the existence of the floating foreign object (spike tip) in the fluid may be psychologically troubling to the patient.
Another type of dual-spiked connector for introducing a secondary fluid into an IV bag is one that eliminates the break-away tip. With this alternative connector, the conduit is in communication with the ambient at both spiked ends. Instead of a breakaway tip, however, this alternative connector employs a plug centrally positioned within the internal conduit to prevent the flow of fluid therethrough until the medical practitioner so desires. After both spikes of the connector are in place, i.e., both have penetrated their respective medical containers, the medical practitioner applies an external compressive force to the plug by squeezing the IV bag. The force applied dislodges the plug, whereby the plug is forced into the secondary fluid container (drug vial).
The use of a push-away plug also presents problems. For example, it has been proven difficult, if not costly, to manufacture a conduit plug that reliably performs as designed. If the conduit plug is made too small, the plug does not exert sufficient frictional force against the interior walls of the internal conduit. Under those circumstances, the ambient pressure from the primary fluid itself may dislodge the primary plug prematurely, causing leakage of fluid intended for a patient. Alternatively, if the conduit plug is too large, the compressive force that is necessary to dislodge the plug is too great. Under those circumstances, the force applied externally to the IV bag may adversely compromise the structural integrity of the bag, again causing life-sustaining fluid to leak.
With either of the above connectors, an inherent problem exists in that once fluid flow is established, it cannot be stopped. That is because neither connector is adapted to control the fluid flow therethrough. Moreover, the configuration of the connectors is such that a fluid-control valve cannot be readily attached to the exposed spike end of the connector. Valves that exist to control the flow of medicinal fluids into an IV bag, such as that shown in U.S. Pat. No. 5,694,686, have male luer fittings that are not designed to connect to a spike (e.g. the CLAVE(copyright) 1000 connector manufactured by ICU Medical, Inc. of San Clemente, Calif. or the pre-slit Injection Site manufactured by McGaw Inc. of Irvine, Calif.) Thus, a device to permit an IV bag to be placed in fluid communication with a wide range of commercially available connectors is needed.
Another problem with the connectors identified above is that manufacturing costs are high. Typically, the connectors are injection molded. To generate the interior conduit of the connector housing, a core pin is used to define the surface of the interior conduit. Due to the extremely high temperatures used in the molding process, there is a tendency of the core pin to float within the liquified housing material during the molding process, creating non-uniform wall thickness, which is unacceptable. Thus, the rejection rate is high, driving up the costs of manufacture.
There is, therefore, a need for a drug access system configured to eliminate break-away or floating parts, to reduce the cost of part manufacture, and to expand the use of connectors to which an IV bag may be attached.
The drug access system of the present invention has several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this invention, as expressed by the claims which follow, its more prominent features will now be discussed briefly.
The present invention is an intravenous drug access system. In one embodiment of the invention, the drug access system includes an IV bag having an inlet (injection) port and an outlet port, whereby the inlet port is a female luer fitting integral with the IV bag. With a female luer fitting integral with the IV bag, any number of one-way valves or needleless syringes may be connected to the female luer fitting to facilitate and control the flow of fluid into or out of the IV bag. With a one-way valve connected to the female luer, the IV bag of the present drug access system may be filled with primary fluid and shipped to the end user for later introduction of a secondary fluid. In this embodiment, breakaway parts and/or push-away plugs are advantageously eliminated.
Where it is desired that the IV bag be filled and shipped without a one-way valve already attached thereto, the integral female luer fitting may be enclosed with a sealed end cap comprising a male luer insert with a closed end. Upon receipt by the end user, the IV bag may be turned upside down to isolate the inlet port away from the contents of the IV bag so that the end cap may be removed and replaced by any valve or connector chosen by the end user. In a variation of this embodiment, the female luer fitting may include a thin, membrane stretched across the opening of the female luer fitting to prevent the flow of fluid therethrough. It is contemplated that the membrane be readily penetrable by the application of a male luer fitting of a valve by the end user when desired. With this latter variation, no end cap is required and the IV bag need not be turned upside down to connect the valve thereto.
The advantage of an integral female luer with an IV bag is that it eliminates the need for a costly conventional dual-spiked connector. However, if a user would prefer to receive IV bags that have conventional inlet ports, an alternative embodiment of the present invention comprises a discrete pre-fabricated connector made with one spike at one end and a female luer fitting at the opposing end. The spike is used to penetrate the IV bag through the conventional inlet port, as with the prior art connectors. Instead of having a second spike, however, an integral female luer is provided that permits connection to a one-way valve or needleless syringe, or any other connector having a male luer fitting. In one variation of this second embodiment, the improved connector includes a protective flange that surrounds, at least in part, the spike to prevent the spike from inadvertently coming into contact with other objects and becoming contaminated when the connector is not in use. In addition, the flange prevents the spike from piercing the skin of a healthcare worker.
There are additional advantages to this second embodiment. In the molding process of the prior art connectors, there were high rejection rates, as explained above. With a connector having a female luer fitting at one end, instead of a second spike, the core pin may be more effectively secured, reducing the likelihood of the core pin floating during the molding process. This results in a reduction in the cost of manufacture, when compared to the molding of prior art connectors. Unlike the prior art connectors, the spike contemplated in the second embodiment of the present invention need not be a closed tip spike. In other words, the spike can be open-ended, permitting immediate backflow of the primary fluid in the IV bag into the interior conduit of the inventive connector. In that instance, the female luer fitting at the other end may be provided with an end cap or thin membrane, as described above, to prevent the fluid from leaking. Upon the connection of a one-way valve or a needleless syringe, fluid flow may be established between a secondary fluid source and the IV bag.